Mahmood Vatankhah | University of Tehran (original) (raw)

Papers by Mahmood Vatankhah

ABSTARCT This study was conducted to evaluate the effects of domestic and imported semens on some... more ABSTARCT This study was conducted to evaluate the effects of domestic and imported semens on some reproductive traits in the Holstein dairy cow's population of the Isfahan dairy farms. A data set containing 99012 records and 3007 semen samples was analyzed by a linear animal mixed model with fixed effects of parity of the dam and herd-year-season and random effects of the direct additive genetic effect of animal, the permanent environmental effect of animal and residual effects. The traits were calving interval, age at first calving, the period from calving to first insemination, service per conception. The overall means of calving interval, days from calving to first insemination, number of services per conception, period of gestation and first calving age were 390.43, 63.64, 2.2, 277.27 and 758.54, respectively. Result from this study showed that the heritability for calving interval, days from calving to first insemination, number of services per conception, period of gestati...

The effect of sodium bicarbonate and magnesium oxide on the fermentation parameters of, rumen mic... more The effect of sodium bicarbonate and magnesium oxide on the fermentation parameters of, rumen microbial population, and carcass characteristics, an experiment was conducted on 18 Lori-Bakhtiari ram lambs. Ammonia nitrogen concentration was significantly different between treatments (p<0.05). Statistical analysis of the data related to right half carcass cuts significant differences between the studied traits (except neck and fat-tail weight) showed (p<0.05). These findings indicted that, under the conditions of this experiment, the adding of 0.2% sodium bicarbonate to the diet, reduced ruminal ammonia nitrogen, pH increasing and improve carcass characteristics of fattening lambs to be.

methods for estimation of colostral immunoglobulin content

The objective of this study was to analyze the effects of factors affecting calving difficulty in... more The objective of this study was to analyze the effects of factors affecting calving difficulty in the Holstein population of the Isfahan dairy farms for subsequent compilation of the model for genetic evaluation as well as for herd management practice. Calving difficulty recorded in 2008-2012 was assessed in five categories1=natural, 2= with the assistance of one person without complications, 3=with the assistance of two persons with some complications, 4= hard pull, with the assistance of three or more persons, with vaginal or neck contusions and5= complicated, with serious difficulties and veterinary assistance required. A data set containing 128259 records were analyzed by a linear model with fixed effects of season, parity of dam, sex of calf. All these effects were significant, and their appropriate categorization was considered. Analyses of additional factors such as gestation length, age at first calving and calf birth weight were performed. The results revealed that gestatio...

ABSTARCT The objective of this study was to analyze the effects of factors affecting reproductive... more ABSTARCT The objective of this study was to analyze the effects of factors affecting reproductive traits in the Holstein population of the Isfahan dairy farms for subsequent compilation of the model for genetic evaluation as well as for herd management practice. A data set containing 99012 records were analyzed by a linear model with fixed effects of year , herd ,season, parity of dam, calving interval, age at first calving, period from calving to first insemination, service per consumption. All these effects were not significant; also their appropriate categorization was considered. Analyses of additional factors such as gestation length, age at first calving and service per consumption were performed. The results revealed that gestation length was in a relationship with Holstein dairy cow’s performance. Data for the calving interval (day) showed that the mean of calving interval in experimental animal is 390.43±58.88 and period of lactation was significant effect on calving interv...

The objective of this study was to analyze the effects of factors affecting calving difficulty in... more The objective of this study was to analyze the effects of factors affecting calving difficulty in the Holstein population of the Isfahan dairy farms for subsequent compilation of the model for genetic evaluation as well as for herd management practice. Calving difficulty recorded in 2008-2012 was assessed in five categories1=natural, 2= with the assistance of one person without complications, 3=with the assistance of two persons with some complications, 4= hard pull, with the assistance of three or more persons, with vaginal or neck contusions and5= complicated, with serious difficulties and veterinary assistance required. A data set containing 128259 records were analyzed by a linear model with fixed effects of season, parity of dam, sex of calf. All these effects were significant, and their appropriate categorization was considered. Analyses of additional factors such as gestation length, age at first calving and calf birth weight were performed. The results revealed that gestatio...

Animal Production Science, 2017

The aim of the present study was to identify the significance of Rayeni Cashmere goat’s socioecon... more The aim of the present study was to identify the significance of Rayeni Cashmere goat’s socioeconomic traits so as to derive economic weights for the selection criteria that can be used easily by goat breeders. A deterministic bio-economic model was used to estimate economic value for adult bodyweight of doe (BWD), annual milk yield (MW), annual cashmere weight (CW), bodyweight of kids sold at 6.5 months (WK), and number of kids sold at 6.5 months per doe (NK). The relative importance of traits was determined on the basis of the estimated economic values, and, consequently, the most beneficial traits were applied to construct selection indices. Five selection indices with different herd sizes and buck ratios were proposed (I1–I5). The traits included in each index were as follows: BWD, MW, CW, WK and NK (I1); MW, CW, WK and NK (I2); BWD, MW, WK and NK (I3); BWD, MW and CW (I4); and BWD, CW, WK and NK (I5). Absolute economic values (US$) of BWD, MW, CW, WK and NK traits were $–0.870,...

Middle East Journal of Scientific Research

The paper examines the spatial dimension of agricultural resources mobilization through agro-base... more The paper examines the spatial dimension of agricultural resources mobilization through agro-based industrial infrastructure in Haryana. In order to analysis the agricultural produce mobilization through related industries, a coefficient of correlation between five major crop-production and related number of agro-based industries has been worked out. The study is based on secondary sources of data, collected from statistical abstract of Haryana indicate a co-related values indicate the inferences of variability in agricultural resource mobilization. The numerical values of coefficient of correlation indicate a regional disparity in varied agricultural production and its produce required by the related agro-based industries. It is therefore, become an imperative to develop industrial infrastructure, and so that the agricultural produce may be mobilized within its vicinal areas. It may also lead to minimization of transport cost for the farmers. As a result, the farmers match fetches a remunerative price for their agricultural produces.

Tropical Animal Health and Production, 2011

Small Ruminant Research, 2013

The data used in this study were 6426 records of Karakul lambs' length of life and survival rate ... more The data used in this study were 6426 records of Karakul lambs' length of life and survival rate from 228 sires and 1894 dams collected from year 1992 to 2009. Linear and hazard ratio models with Weibull function were used in the analyses. Factors included in the models were non-genetic factors of year and month of birth, sex of lamb, type of birth and age of dam and lambs' birth weight fitted as linear and quadratic covariate. Results showed that the overall mean of lamb's life length and cumulative survival rate up to yearling were 274.32 days and 85.43%, respectively. The effect of year, month and type of birth, sex of lamb and lamb's birth weight as linear and quadratic covariates were significant (P < 0.01). However, the effect of age of dam on length of lamb's life and survival rate was not significant (P > 0.05). The survival rate and hazard ratio of lambs born in the first and second lambing month were higher and lower than the third month, respectively. The male lambs had lower survival rate and higher hazard ratio compared with females. Lambs with average birth weight had higher survival rate and lower hazard ratio than lambs with low and high birth weight. Although, lambs born from younger and older dams tended to have lower survival rate and higher hazard ratio, but they had not any significant differences with lambs born from middle age dams. Twin lambs had lower survival rate and higher hazard ratio than single lambs. According to the results obtained in this study, analyzing the effect of non-genetic factors on length of life and survival rate of lambs with linear and survival models produced the same result and these models can be used interchangeably.

Livestock Science, 2012

A number of 10,606 body weight (BW) records of 3908 Raini goats from 153 sires and 1072 dams were... more A number of 10,606 body weight (BW) records of 3908 Raini goats from 153 sires and 1072 dams were used to estimate direct and maternal genetics, direct permanent environmental, and maternal permanent environmental effects on growth from 1 to 410 days of age. The data were collected during 1996 to 2007 from a flock of Raini goat in breeding station in Kerman province; Iran. Random regression (RR) models, including age of dam, sex of kid, type of birth, month and year of birth were used as fixed effects. Also, animal, dam, animal permanent environmental, and maternal permanent environmental as random effects, were fitted to the data using second to fifth order of fit in different combinations of Legendre polynomials for age of kid. Comparisons among different models, based on the Akaike's information criterion, and the Bayesian-Schwarz information criterion were used to select the best model for analyses. The best fitting RRM was the model with a Legendre polynomial of fifth order for direct and maternal genetic effects and fourth order for individual and maternal permanent environmental effects. Direct heritability increased from 0.14 at 20 days of age to 0.38 at 150 days of age then decreased suddenly to 0.18 at 270 days of age and increased thereafter. Maternal heritability increased (except 20 days) to 150 days and then declined moderately until 360 days of age. Genetic correlations among weight at various ages were positive, low to high and ranged from 0.10 between 20 and 360 days of age to 0.99 between 70-90 and 150-180 days of age. The genetic and phenotypic correlations between weights increased with decreasing interval between weights. The low value of genetic correlation (0.10) between early (20 day) and late (360 days) weights implies that early weights are not under the same genetic control as weights at older ages.

Tropical Animal Health and Production, 2013

Genetic parameters were estimated for 6-month weight (W6), 9-month weight (W9), 12-month weight (... more Genetic parameters were estimated for 6-month weight (W6), 9-month weight (W9), 12-month weight (W12), average daily gain from birth to 6 months old (ADG6), and Kleiber ratio at 6 months (KL6) traits using 6,442 records obtained from a Raini Cashmere goat flock. The parameters were estimated using the restricted maximum likelihood procedure and applying four animal models excluding or including maternal additive genetic and permanent environmental effects. Heritability estimates for W6, W9, W12, ADG6, and KL6, under the most appropriate model were 0.028, 0.26, 0.29, 0.02, and 0.25, respectively. The estimates of genetic and phenotypic correlations among W6, W9, W12, and ADG6 were high and ranged from 0.73 to 0.99. The estimates of genetic and phenotypic correlations among KL6 and others traits were negative and low. Thus, these estimates of genetic parameters may provide a basis for deriving selection indices for postweaning growth traits also low genetic correlation between growth traits with KL6, it is possible to increase efficiency in Raini kids by multitrait selection.

High rate of ovulation and litter size are the most important affecting factors in reproduction s... more High rate of ovulation and litter size are the most important affecting factors in reproduction system and subsequently increases economical efficiency in sheep breeding industry. This study was carried out for detection of mutation in FecB and FecXI genes in Lori-Bakhtiari sheep breed. It has been reported that these major genes can increase ovulation and also twining rate in different sheep breed. Blood samples were collected from 165 individual for identification of polymorphisms at these loci. DNA was extracted using modified salting out method. Polymorphism chain reaction (PCR) was used to amplify desired fragments at these loci using two pairs of specific primers. Each of specified primer pairs amplified a fragment with 190 and 154 bp at FecB and FecXI loci, respectively. For genotyping of the samples, the PCR products were electrophoresed on 3% agarose gel after digestion with endonuclease AvaII for FecB and XbaI for FecXI. In the case of mutation, two fragments of 30, 160 an...

Asian Pacific Journal of Reproduction, 2016

Acta Veterinaria Brno, 2013

Journal of Cell and Animal Biology, Apr 30, 2014

Effect of sodium bicarbonate (SB) and magnesium oxide (MgO) in high concentrate fed Lori-Bakhtiar... more Effect of sodium bicarbonate (SB) and magnesium oxide (MgO) in high concentrate fed Lori-Bakhtiari lambs was studied on productive performance and carcass characteristics. Eighteen weaned (90 days old) Lori-Bakhtiari male lambs divided into three equal groups were fed basal diet. Each group received a basal diet for 75 days with one of the following three treatments: (1) no additives (NA); (2) 0.05% magnesium oxide and (3) 0.2% sodium bicarbonate. Lambs were individually confined to 1.5 m 2 metabolic cages. Cold and hot carcass weight (kg) and hot dressing (%) were higher in group receiving MgO than the SB group (p<0.05). There were no significant different (p>0.05) in visceral fat contents (kidney, rumen mesenteric) in lambs of control and treated groups. Body weight (kg) and average daily gain (ADG) was higher in group receiving MgO than the SB group (p<0.05). No effect of MgO or SB in the diet was observed on weight of liver, lungs, blood and lie. Heart weight was greater (p<0.05) for lambs consumed diets supplemented with MgO. The results showed that the use of 0.05% magnesium oxide in the diet can increase dry matter intake, weight gain and improvement is weight and percent carcass than the control group and sodium bicarbonate.

Tropical Animal Health and Production, 2013

Genetic parameters were estimated for 6-month weight (W6), 9-month weight (W9), 12-month weight (... more Genetic parameters were estimated for 6-month weight (W6), 9-month weight (W9), 12-month weight (W12), average daily gain from birth to 6 months old (ADG6), and Kleiber ratio at 6 months (KL6) traits using 6,442 records obtained from a Raini Cashmere goat flock. The parameters were estimated using the restricted maximum likelihood procedure and applying four animal models excluding or including maternal additive genetic and permanent environmental effects. Heritability estimates for W6, W9, W12, ADG6, and KL6, under the most appropriate model were 0.028, 0.26, 0.29, 0.02, and 0.25, respectively. The estimates of genetic and phenotypic correlations among W6, W9, W12, and ADG6 were high and ranged from 0.73 to 0.99. The estimates of genetic and phenotypic correlations among KL6 and others traits were negative and low. Thus, these estimates of genetic parameters may provide a basis for deriving selection indices for postweaning growth traits also low genetic correlation between growth traits with KL6, it is possible to increase efficiency in Raini kids by multitrait selection.

Tropical Animal Health and Production, 2012

Survival records from 1,763 Kermani lambs born between 1996 and 2004 from 294 ewes and 81 rams we... more Survival records from 1,763 Kermani lambs born between 1996 and 2004 from 294 ewes and 81 rams were used to determine genetic and non-genetic factors affecting lamb survival. Traits included were lamb survival across five periods from birth to 7, 14, 56, 70, and 90 days of age. Traits were analyzed under Weibull proportional hazard sire models. Several binary analyses were also conducted using animal models. Statistical models included the fixed class effects of sex of lamb, month and year of birth, a covariate effect of birth weight, and random genetic effects of both sire (in survival analyses) and animal (in binary analyses). The average survival to 90 days of age was 94.8%. Hazard rates ranged from 1.00 (birth to 90 days of age) to 1.73 (birth to 7 days of age) between the two sexes indicating that male lambs were at higher risk of mortality than females (P<0.01). This study also revealed a curvilinear relationship between lamb survival and lamb birth weight, suggesting that viability and birth weight could be considered simultaneously in the selection programs to obtain optimal birth weight in Kermani lambs. Estimates of heritabilities from survival analyses were medium and ranged from 0.23 to 0.29. In addition, heritability estimates obtained from binary analyses were low and varied from 0.04 to 0.09. The results of this study suggest that progress in survival traits could be possible through managerial strategies and genetic selection.

Tropical Animal Health and Production, 2012

Data and pedigree information used in the present study were 3,022 records of kids obtained from ... more Data and pedigree information used in the present study were 3,022 records of kids obtained from the breeding station of Raini goat. The studied traits were birth weight (BW), weaning weight (WW), average daily gain from birth to weaning (ADG) and Kleiber ratio at weaning (KR). The model included the fixed effects of sex of kid, type of birth, age of dam, year of birth, month of birth, and age of kid (days) as covariate that had significant effects, and random effects direct additive genetic, maternal additive genetic, maternal permanent environmental effects and residual. (Co) variance components were estimated using univariate and multivariate analysis by WOMBAT software applying four animal models including and ignoring maternal effects. Likelihood ratio test used to determine the most appropriate models. Heritability (h(a)(2)) estimates for BW, WW, ADG, and KR according to suitable model were 0.12 ± 0.05, 0.08 ± 0.06, 0.10 ± 0.06, and 0.06 ± 0.05, respectively. Estimates of the proportion of maternal permanent environmental effect to phenotypic variance (c(2)) were 0.17 ± 0.03, 0.07 ± 0.03, and 0.07 ± 0.03 for BW, WW, and ADG, respectively. Genetic correlations among traits were positive and ranged from 0.53 (BW-ADG) to 1.00 (WW-ADG, WW-KR, and ADG-KR). The maternal permanent environmental correlations between BW-WW, BW-ADG, and WW-ADG were 0.54, 0.48, and 0.99, respectively. Results indicated that maternal effects, especially maternal permanent environmental effects are an important source of variation in pre-weaning growth trait and ignoring those in the model redound incorrect genetic evaluation of kids.

Tropical Animal Health and Production, 2012

Genetic parameters and genetic trends for birth weight (BW), weaning weight (WW), 6-month weight ... more Genetic parameters and genetic trends for birth weight (BW), weaning weight (WW), 6-month weight (6MW), and yearling weight (YW) traits were estimated by using records of 5,634 Makooei lambs, descendants of 289 sires and 1,726 dams, born between 1996 and 2009 at the Makooei sheep breeding station, West Azerbaijan, Iran. The (co)variance components were estimated with different animal models using a restricted maximum likelihood procedure and the most appropriate model for each trait was determined by Akaike&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s Information Criterion. Breeding values of animals were predicted with best linear unbiased prediction methodology under multi-trait animal models and genetic trends were estimated by regression mean breeding values on birth year. The most appropriate model for BW was a model including direct and maternal genetic effects, regardless of their covariance. The model for WW and 6MW included direct additive genetic effects. The model for YW included direct genetic effects only. Direct heritabilities based on the best model were estimated 0.15 ± 0.04, 0.16 ± 0.03, 0.21 ± 0.04, and 0.22 ± 0.06 for BW, WW, 6MW, and YW, respectively, and maternal heritability obtained 0.08 ± 0.02 for BW. Genetic correlations among the traits were positive and varied from 0.28 for BW-YW to 0.66 for BW-WW and phenotypic correlations were generally lower than the genetic correlations. Genetic trends were 8.1 ± 2, 67.4 ± 5, 38.7 ± 4, and 47.6 ± 6 g per year for BW, WW, 6MW, and YW, respectively.

ABSTARCT This study was conducted to evaluate the effects of domestic and imported semens on some... more ABSTARCT This study was conducted to evaluate the effects of domestic and imported semens on some reproductive traits in the Holstein dairy cow's population of the Isfahan dairy farms. A data set containing 99012 records and 3007 semen samples was analyzed by a linear animal mixed model with fixed effects of parity of the dam and herd-year-season and random effects of the direct additive genetic effect of animal, the permanent environmental effect of animal and residual effects. The traits were calving interval, age at first calving, the period from calving to first insemination, service per conception. The overall means of calving interval, days from calving to first insemination, number of services per conception, period of gestation and first calving age were 390.43, 63.64, 2.2, 277.27 and 758.54, respectively. Result from this study showed that the heritability for calving interval, days from calving to first insemination, number of services per conception, period of gestati...

The effect of sodium bicarbonate and magnesium oxide on the fermentation parameters of, rumen mic... more The effect of sodium bicarbonate and magnesium oxide on the fermentation parameters of, rumen microbial population, and carcass characteristics, an experiment was conducted on 18 Lori-Bakhtiari ram lambs. Ammonia nitrogen concentration was significantly different between treatments (p<0.05). Statistical analysis of the data related to right half carcass cuts significant differences between the studied traits (except neck and fat-tail weight) showed (p<0.05). These findings indicted that, under the conditions of this experiment, the adding of 0.2% sodium bicarbonate to the diet, reduced ruminal ammonia nitrogen, pH increasing and improve carcass characteristics of fattening lambs to be.

methods for estimation of colostral immunoglobulin content

The objective of this study was to analyze the effects of factors affecting calving difficulty in... more The objective of this study was to analyze the effects of factors affecting calving difficulty in the Holstein population of the Isfahan dairy farms for subsequent compilation of the model for genetic evaluation as well as for herd management practice. Calving difficulty recorded in 2008-2012 was assessed in five categories1=natural, 2= with the assistance of one person without complications, 3=with the assistance of two persons with some complications, 4= hard pull, with the assistance of three or more persons, with vaginal or neck contusions and5= complicated, with serious difficulties and veterinary assistance required. A data set containing 128259 records were analyzed by a linear model with fixed effects of season, parity of dam, sex of calf. All these effects were significant, and their appropriate categorization was considered. Analyses of additional factors such as gestation length, age at first calving and calf birth weight were performed. The results revealed that gestatio...

ABSTARCT The objective of this study was to analyze the effects of factors affecting reproductive... more ABSTARCT The objective of this study was to analyze the effects of factors affecting reproductive traits in the Holstein population of the Isfahan dairy farms for subsequent compilation of the model for genetic evaluation as well as for herd management practice. A data set containing 99012 records were analyzed by a linear model with fixed effects of year , herd ,season, parity of dam, calving interval, age at first calving, period from calving to first insemination, service per consumption. All these effects were not significant; also their appropriate categorization was considered. Analyses of additional factors such as gestation length, age at first calving and service per consumption were performed. The results revealed that gestation length was in a relationship with Holstein dairy cow’s performance. Data for the calving interval (day) showed that the mean of calving interval in experimental animal is 390.43±58.88 and period of lactation was significant effect on calving interv...

The objective of this study was to analyze the effects of factors affecting calving difficulty in... more The objective of this study was to analyze the effects of factors affecting calving difficulty in the Holstein population of the Isfahan dairy farms for subsequent compilation of the model for genetic evaluation as well as for herd management practice. Calving difficulty recorded in 2008-2012 was assessed in five categories1=natural, 2= with the assistance of one person without complications, 3=with the assistance of two persons with some complications, 4= hard pull, with the assistance of three or more persons, with vaginal or neck contusions and5= complicated, with serious difficulties and veterinary assistance required. A data set containing 128259 records were analyzed by a linear model with fixed effects of season, parity of dam, sex of calf. All these effects were significant, and their appropriate categorization was considered. Analyses of additional factors such as gestation length, age at first calving and calf birth weight were performed. The results revealed that gestatio...

Animal Production Science, 2017

The aim of the present study was to identify the significance of Rayeni Cashmere goat’s socioecon... more The aim of the present study was to identify the significance of Rayeni Cashmere goat’s socioeconomic traits so as to derive economic weights for the selection criteria that can be used easily by goat breeders. A deterministic bio-economic model was used to estimate economic value for adult bodyweight of doe (BWD), annual milk yield (MW), annual cashmere weight (CW), bodyweight of kids sold at 6.5 months (WK), and number of kids sold at 6.5 months per doe (NK). The relative importance of traits was determined on the basis of the estimated economic values, and, consequently, the most beneficial traits were applied to construct selection indices. Five selection indices with different herd sizes and buck ratios were proposed (I1–I5). The traits included in each index were as follows: BWD, MW, CW, WK and NK (I1); MW, CW, WK and NK (I2); BWD, MW, WK and NK (I3); BWD, MW and CW (I4); and BWD, CW, WK and NK (I5). Absolute economic values (US$) of BWD, MW, CW, WK and NK traits were $–0.870,...

Middle East Journal of Scientific Research

The paper examines the spatial dimension of agricultural resources mobilization through agro-base... more The paper examines the spatial dimension of agricultural resources mobilization through agro-based industrial infrastructure in Haryana. In order to analysis the agricultural produce mobilization through related industries, a coefficient of correlation between five major crop-production and related number of agro-based industries has been worked out. The study is based on secondary sources of data, collected from statistical abstract of Haryana indicate a co-related values indicate the inferences of variability in agricultural resource mobilization. The numerical values of coefficient of correlation indicate a regional disparity in varied agricultural production and its produce required by the related agro-based industries. It is therefore, become an imperative to develop industrial infrastructure, and so that the agricultural produce may be mobilized within its vicinal areas. It may also lead to minimization of transport cost for the farmers. As a result, the farmers match fetches a remunerative price for their agricultural produces.

Tropical Animal Health and Production, 2011

Small Ruminant Research, 2013

The data used in this study were 6426 records of Karakul lambs' length of life and survival rate ... more The data used in this study were 6426 records of Karakul lambs' length of life and survival rate from 228 sires and 1894 dams collected from year 1992 to 2009. Linear and hazard ratio models with Weibull function were used in the analyses. Factors included in the models were non-genetic factors of year and month of birth, sex of lamb, type of birth and age of dam and lambs' birth weight fitted as linear and quadratic covariate. Results showed that the overall mean of lamb's life length and cumulative survival rate up to yearling were 274.32 days and 85.43%, respectively. The effect of year, month and type of birth, sex of lamb and lamb's birth weight as linear and quadratic covariates were significant (P < 0.01). However, the effect of age of dam on length of lamb's life and survival rate was not significant (P > 0.05). The survival rate and hazard ratio of lambs born in the first and second lambing month were higher and lower than the third month, respectively. The male lambs had lower survival rate and higher hazard ratio compared with females. Lambs with average birth weight had higher survival rate and lower hazard ratio than lambs with low and high birth weight. Although, lambs born from younger and older dams tended to have lower survival rate and higher hazard ratio, but they had not any significant differences with lambs born from middle age dams. Twin lambs had lower survival rate and higher hazard ratio than single lambs. According to the results obtained in this study, analyzing the effect of non-genetic factors on length of life and survival rate of lambs with linear and survival models produced the same result and these models can be used interchangeably.

Livestock Science, 2012

A number of 10,606 body weight (BW) records of 3908 Raini goats from 153 sires and 1072 dams were... more A number of 10,606 body weight (BW) records of 3908 Raini goats from 153 sires and 1072 dams were used to estimate direct and maternal genetics, direct permanent environmental, and maternal permanent environmental effects on growth from 1 to 410 days of age. The data were collected during 1996 to 2007 from a flock of Raini goat in breeding station in Kerman province; Iran. Random regression (RR) models, including age of dam, sex of kid, type of birth, month and year of birth were used as fixed effects. Also, animal, dam, animal permanent environmental, and maternal permanent environmental as random effects, were fitted to the data using second to fifth order of fit in different combinations of Legendre polynomials for age of kid. Comparisons among different models, based on the Akaike's information criterion, and the Bayesian-Schwarz information criterion were used to select the best model for analyses. The best fitting RRM was the model with a Legendre polynomial of fifth order for direct and maternal genetic effects and fourth order for individual and maternal permanent environmental effects. Direct heritability increased from 0.14 at 20 days of age to 0.38 at 150 days of age then decreased suddenly to 0.18 at 270 days of age and increased thereafter. Maternal heritability increased (except 20 days) to 150 days and then declined moderately until 360 days of age. Genetic correlations among weight at various ages were positive, low to high and ranged from 0.10 between 20 and 360 days of age to 0.99 between 70-90 and 150-180 days of age. The genetic and phenotypic correlations between weights increased with decreasing interval between weights. The low value of genetic correlation (0.10) between early (20 day) and late (360 days) weights implies that early weights are not under the same genetic control as weights at older ages.

Tropical Animal Health and Production, 2013

Genetic parameters were estimated for 6-month weight (W6), 9-month weight (W9), 12-month weight (... more Genetic parameters were estimated for 6-month weight (W6), 9-month weight (W9), 12-month weight (W12), average daily gain from birth to 6 months old (ADG6), and Kleiber ratio at 6 months (KL6) traits using 6,442 records obtained from a Raini Cashmere goat flock. The parameters were estimated using the restricted maximum likelihood procedure and applying four animal models excluding or including maternal additive genetic and permanent environmental effects. Heritability estimates for W6, W9, W12, ADG6, and KL6, under the most appropriate model were 0.028, 0.26, 0.29, 0.02, and 0.25, respectively. The estimates of genetic and phenotypic correlations among W6, W9, W12, and ADG6 were high and ranged from 0.73 to 0.99. The estimates of genetic and phenotypic correlations among KL6 and others traits were negative and low. Thus, these estimates of genetic parameters may provide a basis for deriving selection indices for postweaning growth traits also low genetic correlation between growth traits with KL6, it is possible to increase efficiency in Raini kids by multitrait selection.

High rate of ovulation and litter size are the most important affecting factors in reproduction s... more High rate of ovulation and litter size are the most important affecting factors in reproduction system and subsequently increases economical efficiency in sheep breeding industry. This study was carried out for detection of mutation in FecB and FecXI genes in Lori-Bakhtiari sheep breed. It has been reported that these major genes can increase ovulation and also twining rate in different sheep breed. Blood samples were collected from 165 individual for identification of polymorphisms at these loci. DNA was extracted using modified salting out method. Polymorphism chain reaction (PCR) was used to amplify desired fragments at these loci using two pairs of specific primers. Each of specified primer pairs amplified a fragment with 190 and 154 bp at FecB and FecXI loci, respectively. For genotyping of the samples, the PCR products were electrophoresed on 3% agarose gel after digestion with endonuclease AvaII for FecB and XbaI for FecXI. In the case of mutation, two fragments of 30, 160 an...

Asian Pacific Journal of Reproduction, 2016

Acta Veterinaria Brno, 2013

Journal of Cell and Animal Biology, Apr 30, 2014

Effect of sodium bicarbonate (SB) and magnesium oxide (MgO) in high concentrate fed Lori-Bakhtiar... more Effect of sodium bicarbonate (SB) and magnesium oxide (MgO) in high concentrate fed Lori-Bakhtiari lambs was studied on productive performance and carcass characteristics. Eighteen weaned (90 days old) Lori-Bakhtiari male lambs divided into three equal groups were fed basal diet. Each group received a basal diet for 75 days with one of the following three treatments: (1) no additives (NA); (2) 0.05% magnesium oxide and (3) 0.2% sodium bicarbonate. Lambs were individually confined to 1.5 m 2 metabolic cages. Cold and hot carcass weight (kg) and hot dressing (%) were higher in group receiving MgO than the SB group (p<0.05). There were no significant different (p>0.05) in visceral fat contents (kidney, rumen mesenteric) in lambs of control and treated groups. Body weight (kg) and average daily gain (ADG) was higher in group receiving MgO than the SB group (p<0.05). No effect of MgO or SB in the diet was observed on weight of liver, lungs, blood and lie. Heart weight was greater (p<0.05) for lambs consumed diets supplemented with MgO. The results showed that the use of 0.05% magnesium oxide in the diet can increase dry matter intake, weight gain and improvement is weight and percent carcass than the control group and sodium bicarbonate.

Tropical Animal Health and Production, 2013

Genetic parameters were estimated for 6-month weight (W6), 9-month weight (W9), 12-month weight (... more Genetic parameters were estimated for 6-month weight (W6), 9-month weight (W9), 12-month weight (W12), average daily gain from birth to 6 months old (ADG6), and Kleiber ratio at 6 months (KL6) traits using 6,442 records obtained from a Raini Cashmere goat flock. The parameters were estimated using the restricted maximum likelihood procedure and applying four animal models excluding or including maternal additive genetic and permanent environmental effects. Heritability estimates for W6, W9, W12, ADG6, and KL6, under the most appropriate model were 0.028, 0.26, 0.29, 0.02, and 0.25, respectively. The estimates of genetic and phenotypic correlations among W6, W9, W12, and ADG6 were high and ranged from 0.73 to 0.99. The estimates of genetic and phenotypic correlations among KL6 and others traits were negative and low. Thus, these estimates of genetic parameters may provide a basis for deriving selection indices for postweaning growth traits also low genetic correlation between growth traits with KL6, it is possible to increase efficiency in Raini kids by multitrait selection.

Tropical Animal Health and Production, 2012

Survival records from 1,763 Kermani lambs born between 1996 and 2004 from 294 ewes and 81 rams we... more Survival records from 1,763 Kermani lambs born between 1996 and 2004 from 294 ewes and 81 rams were used to determine genetic and non-genetic factors affecting lamb survival. Traits included were lamb survival across five periods from birth to 7, 14, 56, 70, and 90 days of age. Traits were analyzed under Weibull proportional hazard sire models. Several binary analyses were also conducted using animal models. Statistical models included the fixed class effects of sex of lamb, month and year of birth, a covariate effect of birth weight, and random genetic effects of both sire (in survival analyses) and animal (in binary analyses). The average survival to 90 days of age was 94.8%. Hazard rates ranged from 1.00 (birth to 90 days of age) to 1.73 (birth to 7 days of age) between the two sexes indicating that male lambs were at higher risk of mortality than females (P<0.01). This study also revealed a curvilinear relationship between lamb survival and lamb birth weight, suggesting that viability and birth weight could be considered simultaneously in the selection programs to obtain optimal birth weight in Kermani lambs. Estimates of heritabilities from survival analyses were medium and ranged from 0.23 to 0.29. In addition, heritability estimates obtained from binary analyses were low and varied from 0.04 to 0.09. The results of this study suggest that progress in survival traits could be possible through managerial strategies and genetic selection.

Tropical Animal Health and Production, 2012

Data and pedigree information used in the present study were 3,022 records of kids obtained from ... more Data and pedigree information used in the present study were 3,022 records of kids obtained from the breeding station of Raini goat. The studied traits were birth weight (BW), weaning weight (WW), average daily gain from birth to weaning (ADG) and Kleiber ratio at weaning (KR). The model included the fixed effects of sex of kid, type of birth, age of dam, year of birth, month of birth, and age of kid (days) as covariate that had significant effects, and random effects direct additive genetic, maternal additive genetic, maternal permanent environmental effects and residual. (Co) variance components were estimated using univariate and multivariate analysis by WOMBAT software applying four animal models including and ignoring maternal effects. Likelihood ratio test used to determine the most appropriate models. Heritability (h(a)(2)) estimates for BW, WW, ADG, and KR according to suitable model were 0.12 ± 0.05, 0.08 ± 0.06, 0.10 ± 0.06, and 0.06 ± 0.05, respectively. Estimates of the proportion of maternal permanent environmental effect to phenotypic variance (c(2)) were 0.17 ± 0.03, 0.07 ± 0.03, and 0.07 ± 0.03 for BW, WW, and ADG, respectively. Genetic correlations among traits were positive and ranged from 0.53 (BW-ADG) to 1.00 (WW-ADG, WW-KR, and ADG-KR). The maternal permanent environmental correlations between BW-WW, BW-ADG, and WW-ADG were 0.54, 0.48, and 0.99, respectively. Results indicated that maternal effects, especially maternal permanent environmental effects are an important source of variation in pre-weaning growth trait and ignoring those in the model redound incorrect genetic evaluation of kids.

Tropical Animal Health and Production, 2012

Genetic parameters and genetic trends for birth weight (BW), weaning weight (WW), 6-month weight ... more Genetic parameters and genetic trends for birth weight (BW), weaning weight (WW), 6-month weight (6MW), and yearling weight (YW) traits were estimated by using records of 5,634 Makooei lambs, descendants of 289 sires and 1,726 dams, born between 1996 and 2009 at the Makooei sheep breeding station, West Azerbaijan, Iran. The (co)variance components were estimated with different animal models using a restricted maximum likelihood procedure and the most appropriate model for each trait was determined by Akaike&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s Information Criterion. Breeding values of animals were predicted with best linear unbiased prediction methodology under multi-trait animal models and genetic trends were estimated by regression mean breeding values on birth year. The most appropriate model for BW was a model including direct and maternal genetic effects, regardless of their covariance. The model for WW and 6MW included direct additive genetic effects. The model for YW included direct genetic effects only. Direct heritabilities based on the best model were estimated 0.15 ± 0.04, 0.16 ± 0.03, 0.21 ± 0.04, and 0.22 ± 0.06 for BW, WW, 6MW, and YW, respectively, and maternal heritability obtained 0.08 ± 0.02 for BW. Genetic correlations among the traits were positive and varied from 0.28 for BW-YW to 0.66 for BW-WW and phenotypic correlations were generally lower than the genetic correlations. Genetic trends were 8.1 ± 2, 67.4 ± 5, 38.7 ± 4, and 47.6 ± 6 g per year for BW, WW, 6MW, and YW, respectively.